Luther Burbank Experiment Farm Self-Guided Tour

Note: Copies of the self-guided tour, listed below, can be found at several locations at the farm: in the kiosk at the main parking lot; on the outside wall of the barn; and inside the decorative mailbox at the front of the Burbank cottage.

Tour Map

After decades of neglect, Burbank’s experiment grounds were overgrown with blackberries and poison oak. As the weeds were cleared out, rows of unusual plants appeared. These mature plants in north-south rows are the remains of Luther Burbank’s experiments.

 As you tour the grounds, please note that plants marked with an asterisk ( ) are original plantings on the property prior to restoration. Others have been introduced in recent years.

 #1 Royal Hybrid Black Walnut (Juglans ‘Royal’) ✼  This Burbank introduction (1893) is a hybrid of California black walnut (J. Hindsii) and eastern walnut (J. nigra). The oldest tree on the Farm (1885) it was planted as a “witness tree,” a property line marker. This variety is a heavy producer. 

#2 White-fruited Blackberry ( Rubus ‘Snowbank’)  Introduced in 1916 as an improved form of his original white blackberry, ‘Iceberg’ (1894). Developed as something of a joke, it nonetheless represents a remarkable achievement. 

#3 Grape ( Vitis vinifera ) ✼ Portions of a long row of grapes remain on the Farm. These are all table grapes. Being a teetotaler, Burbank never developed any grapes for wine production. 

#4 Service Tree (Sorbus domestica ) ✼ This relative of the apple is drought, disease and pest resistant. Burbank doubled the size of the fruit, which resembles tiny pears borne in large clusters, but never developed its delectability. Fruit must be ripened off the tree (bletted) to be edible. Notice these trees in their original north-south rows. 

#5 Chestnut ( Castanea hybrid ) ✼ Burbank developed hybrid chestnuts from European, Japanese and Chinese species to increase their resistance to chestnut blight. This tree produces abundant crops of tasty, burr-covered nuts that are prized both by squirrels and humans. Another row stands at the north end of the farm. 

# 6 Paradox Walnut ( Juglans x paradox ‘Burbank’ ) ✼ Introduced in 1893. (North twin) Burbank developed this fast-growing lumber tree (it requires only 15 years to mature instead of the usual 50 to 60 years) by hybridizing the English walnut (#9) with the California black walnut (South twin). It is commonly used today as rootstock. 

#7 Van Deman Quince ( Cydonia oblonga ‘Van Deman’) ✼ A popular Burbank hybrid introduced in 1893. Fruit is squat, pear-shaped, fuzzy and delicious when fully ripened and cooked. Named for Dr. H. E. Van Deman of the USDA. 

#8 Wild Black Cherry ( Prunus serotina ) ✼ Native to eastern North America, this is one of many cherry species grown by Burbank for use in developing new hybrid cherries. He also grew the native Western Chokecherry (Prunus virginiana demissa) and various evergreen cherries. (see #31). 

#9 Multi-grafted English Walnut ( Juglans regia ) ✼ A “mother” tree used as understock for grafting hybrid walnut seedlings so they would grow and bear nuts more quickly. Each major branch carries a different variety. 

#10 Burbank Hybrid Fruit Trees This contemporary orchard is composed of Burbank hybrid plums, pears, peaches, and apples. Also, plumcots (plum-apricot hybrids, introduced in 1914). Tags identify the different grafted branches. 

#11 Pineapple Quince ( Cydonia oblonga ‘ Pineapple’) The product of fifteen years of selective breeding introduced in 1899, it is still sold in nurseries. When well-ripe it can be eaten like an apple. 

#12 Seedling Avocado ( Persea americana ) Grown from the seed of an original Burbank selection, a huge old tree in Santa Rosa. Well adapted to local climate, it bore small but tasty fruit. 

#13 Himalayan Blackberry ( Rubus ‘Himalaya’) ✼ A second-generation seedling selected from seed imported by Burbank from India. Heavy crops of large, tasty fruit. Notoriously vigorous. Several clones have naturalized from California to Washington State. 

#14 Winterstein Apple ( Malu s domestica ‘Winterstein’) A Gravenstein seedling, it ripens much later, and is a bit sweeter. Selected by Burbank in 1898. 

#15 Burbank Cherry ( Prunus avium ‘Burbank’) Introduced in 1903 the ‘Burbank’ was an important shipping variety for nearly 40 years. 

#16 Apple Espalier ( Malus hybrids) A project of the California Rare Fruit Growers (CRFG). 27 antique apple varieties have been grafted to create an espalier fence design. Behind is Burbank’s yellow-and-red flowered Scotch Broom. 

#17 Multi-Grafted Apple ( Malus hybrids) Another CRFG project begun in 1999. Twenty-five different varieties were grafted on to this mother tree; not all have survived. 

#18 American Persimmon ( Diospyros virginiana ) ✼ American natives that bear abundant, small, edible fruit in the fall. Fruit is sweet and tasty if fully ripened. 

#19 Japanese Persimmon ( Diospyros kaki ‘Tamopan’) ✼ The better-known persimmon, renowned for its large, edible fruit that ripens in late fall. 

#20 Chinese Hawthorn ( Crataegus pinnatifida hybrids) ✼ Burbank hybrids that bear large (1”) edible, scarlet fruit in fall. Part of experiments to develop hawthorns (related to apples and pears) as hardy orchard fruits. Thornless. 

#21 Mexican Hawthorn ( Crataegus Mexicana ) ✼ Hardy, deciduous tree. Bears large (1”) yellow, tasty fruit in the fall. Vicious thorns. 

#22 Wisteria ( Wisteria sinensis ) ✼ Burbank did not introduce any wisteria to the nursery trade. This vine was found growing here during early restoration of the Farm, so it is assumed that Burbank was growing it for experimentation. It has climbed to the top of the Coast Live Oak. 

#23 Blueberry ( Vaccinium corymbosum ) ✼ Perhaps remnants of Burbank’s experiments crossing a West African blueberry with one native to the western U.S. 

#24 Golden Bamboo ( Phyllostachys aurea ) ✼ Burbank noted this plant on a 1914 bill of sale and on his 1916 map. Owing to its infrequency of bloom (every 60-80 years) it probably wasn’t being hybridized by him. 

#25 Thornless Blackberry ( Rubus ‘Sebastopol’) ✼ The first Thornless Blackberries were selected from more than 10,000 seedlings. Here, growing in a dry area, the fruit is undersized. 

#26 Trifoliate Orange ( Poncirus trifoliata ) ✼ Viciously thorny trees from China. Hardy to 15 below zero F; used by Burbank in his (unsuccessful) experiments to develop cold-hardy citrus. Fuzzy fruits have about the same size, hardness and juiciness as golf balls. 

#27 Black Locust ( Robinia pseudoacacia ) ✼ Fast-growing hybrids developed by Burbank for use of its leaves and seed pods as cattle fodder. Note: European Mistletoe (Viscum album) that has colonized here. It is a semi parasite purposely introduced by Burbank for reasons known only to him. 

#28 Oso Berry ( Oemleria cerasiformis ) ✼ Burbank selection (1918) of a hardy, deciduous, drought-tolerant native shrub. Bears bean-sized, edible, blue-black fruit. 

#29 Chinese Quince ( Pseudocydonia sinensis ) ✼ Growing in its original north–south nursery row, this sturdy Burbank hybrid bears smooth, yellow fruit of about the size and shape of a mango. Edible when ripened, cooked and made into preserves. The bark is particularly interesting, shedding and changing color in the spring.

#30 French Hybrid Lilacs ( Syringa vulgaris ) ✼ These remnants of Burbank experiments were never introduced into the nursery trade. Fragrant hybrids bear both single and double flowers of pink, lavender, blue and white. 

#31 Evergreen Cherries ( Prunus hybrids) ✼ Bred from native trees that bear edible, cherry-sized fruit (mostly pit). Useful as ornamentals. Burbank used the three species, caroliniana, ilicifolia, and lyonii in his experiments to develop new hybrid cherries. 

#32 Kentucky Coffee Tree ( Gymnocladus dioicus ) ✼ A native of eastern U.S., its fruits were used as a coffee substitute. Burbank grew it because of his interest in unusual edible species. 

#33 Amarcrinum (x Amarcrinum memoria-corsii ) A true hybrid, the result of crossing the Naked Lady, Amaryllis belladonna and Crinum moorei, both seen growing here. Resembles Crinum by being evergreen, but the pink, fragrant flowers resemble the Naked Lady. 

#34 Apple Blossom Rose ( Rosa ‘Apple Blossom’) Introduced posthumously in 1932. A rambler that bears single pink flowers in large clusters. It is trained here in the pillar style. 

#35 Canna ( Canna x generalis ‘Yellow King Humbert’) Introduced in 1918. Almost identical to ‘King Humbert’ but with yellow flowers dotted red. 

#36 Rhubarb ( Rheum rhabarbarum ‘Crimson Winter’) An improved variety of the cold-tender evergreen rhubarb which Burbank went to great lengths to import from Australia. 

#37 Shasta Daisy Collection ( Leucanthemum × superbum ) The first of this new species of flower was introduced in 1901. In 2001 to commemorate the centennial anniversary, volunteers began this collection of many varieties. 

#38 Surprise Daylily ( Hemerocallis ‘Surprise’) Luther Burbank introduced the ‘Surprise Daylily’ in 1917. 

#39 Burbank Rose ( Rosa ‘Burbank’) Introduced by Burbank in 1899 and was awarded a gold medal at the Louisiana Purchase Exposition in 1904. A repeat bloomer with fragrant, pink flowers. Flower stems normally droop, in the style of the period. 

#40 Blushing Beauty Rose ( Rosa ‘Blushing Beauty’) A Burbank hybrid introduced posthumously in 1934. A vigorous climber with semi-double shell-pink flowers appearing in spring. 

#41 Poker Plant ( Kniphofia ‘Tower of Gold’) This hardy drought-resistant perennial bears yellow flowers in contrast to the more common orange flowered Red Hot Poker Plant. 

#42 Black Walnut ( Juglans nigra hybrid) ✼ A hybrid of U.S. native eastern black walnuts. Beginning in the 1880s, Burbank was among the first hybridizers of American walnuts. Compare with #1 and #9 as to differences in leaves, nuts and bark. 

#43 Catalpa ( Catalpa bignonioides ) ✼ A hardy deciduous native to the Southeastern US. Bell shaped, orchid-like white flowers with purple and yellow inner spotting cover the tree in late spring. Seedpods are long and bean shaped. 

#44 Spineless Cactus ( Opuntia hybrid) Burbank introduced about 60 varieties of spineless cacti. He hoped that they could be used for livestock fodder and turn the desert into rangeland. Some are grown for their fruit, prickly pears.